Mark Cuthbert/UK Press via Getty Images(LONDON) -- Kate Middleton’s last solo royal engagement before she gives birth to her first child next month involved the smashing of a champagne bottle.

The Duchess of Cambridge, 31, fulfilled a royal tradition on Thursday by becoming another in the long line of royal women to christen a cruise ship -- in her case, Princess Cruises’ newest ship, the 3,600-passenger Royal Princess.

Duchess Kate, appearing solo without husband Prince William, wore a leopard print coat by Hobbs, a popular chain retailer in the U.K., that highlighted her growing baby bump. She also maintained the high fashion she’s sported throughout her pregnancy by wearing black high heels and a black fascinator hat.

The duchess, due to give birth in July, told the gathered guests, “I name this ship Royal Princess, may God bless her and all who sail in her,” before cutting the rope.

The traditional Champagne bottle was then released and sent swinging into the ship’s hull, smashing to a large cheer from the crowd and a slight wince from the duchess.

Duchess Kate is part of a long cruise ship tradition of choosing godmothers “to bring good fortune to the ship and its passengers while at sea,” Karen Candy, spokesperson for Princess Cruises, told ABC News in April when it was announced that Kate would be the ship’s godmother.

Princess Diana, Kate’s late mother-in-law, christened a cruise ship at the same spot in Southampton in 1984.